The present invention relates to thermal printing devices and, more particularly, to thermal printing digital postage meters and thermal ink cassettes therefor.
U.S. Pat. No. 5,300,953, entitled THERMAL RIBBON CASSETTE TENSION CONTROL FOR A THERMAL POSTAGE METER describes a thermal printing cassette particularly suited for application with a digital thermal printing postage meter system. In empirical evaluation of the thermal printing cassette described in U.S. Pat. No. 5,300,953, it has been determined that thermal transfer ribbon cassettes exhibited non-linear torque requirements for the cassette drive system as described in U.S. Pat. No. 5,300,953 over the change in radius of the cassette supply spool which was considered disadvantageous.